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1st half of 2016 warmest on record

The 6-month period from January to June was our planet’s warmest half-year in the modern temperature record, which dates to 1880.

According to a report from NASA on Monday (July 19, 2016) two key indicators of climate change – global surface temperatures and Arctic sea ice extent – have broken records in the first half of 2016.

Each of the first six months of 2016 set a record as the warmest respective month globally in the modern temperature record, which dates to 1880, according to scientists at NASA’s Goddard Institute for Space Studies (GISS) in New York. Also, the six-month period as a whole – from January to June – was the warmest half-year on record. The average temperature for the 2016’s first half was 1.3 degrees Celsius (2.4 degrees F.) warmer than the late nineteenth century.

Another record that was broken in 2016’s first half is the Arctic sea ice extent – the measurement of the area of the Arctic Ocean where there is at least some sea ice. Five of the first six months of 2016 set records for the smallest respective monthly Arctic sea ice extent since satellites started keeping track in 1979, according to NASA analyses. The one exception, March, recorded the second smallest extent for that month.

While these two key climate indicators have broken records in 2016, NASA scientists said it is more significant that global temperature and Arctic sea ice are continuing their decades-long trends of change. Both trends are ultimately driven by rising concentrations of heat-trapping carbon dioxide and other greenhouse gases in the atmosphere.

Chunks of sea ice, melt ponds and open water are all seen in this image captured at an altitude of 1,500 feet by the NASA’s Digital Mapping System instrument during an Operation IceBridge flight over the Chukchi Sea on Saturday, July 16, 2016. Image via NASA/Goddard/Operation IceBridge”

The extent of Arctic sea ice at the peak of the summer melt season now covers about 40 percent less area than it did in the late 1970s and early 1980s, says NASA. Arctic sea ice extent in September, the seasonal low point in the annual cycle, has been declining at a rate of 13.4 percent per decade.

Walt Meier is a sea ice scientist at NASA Goddard. He said that he global trend in rising temperatures is outpaced by the regional warming in the Arctic. Meier said:

It has been a record year so far for global temperatures, but the record high temperatures in the Arctic over the past six months have been even more extreme. This warmth as well as unusual weather patterns have led to the record low sea ice extents so far this year.

Eleanor Imster has helped write and edit EarthSky since 1995. She was an integral part of the award-winning EarthSky radio series almost since it began until it ended in 2013. Today, as Lead Editor at EarthSky.org, she helps present the science and nature stories and photos you enjoy. She also serves as one of the voices of EarthSky on social media platforms including Facebook, Twitter and G+. She and her husband live in Tennessee and have two grown sons.